Herzog & de Meuron: The Beijing Olympics made this firm's "Birds' Nest" stadium an instant icon; its "Hanging Gardens of Babylon" design for the Miami Art Museum shows range.

Zaha Hadid: A sexy little pop-up pavilion for Chanel. An ice-sculpture-like design for the Nordpark Cable Railway. A trippy design for the Guggenheim Hermitage in Vilnius. Hadid's work is consistently jaw-dropping.

Rem Koolhaas's OMA: You have to love a guy who can design both a giant headquarters building for China's CCTV and catwalks for Prada.

Steven Holl: His "Linked Hybrid" complex in Beijing, which opened last fall, shows genius and technological virtuosity. Even Holl's smaller projects — say, Kansas City's Nelson Atkins Museum of Art — can be breathtaking in their simple majesty.

Foster + Partners: A double-decker bus for London, an ethereal bridge in France, and the world's most advanced airport terminal in Beijing show the range and global fluency of this British stalwart.

Renzo Piano: The firm's plan for the California Academy of Sciences, with its undulating roof, is a triumph of green design. Another contribution: The New York Times' new headquarters, which the paper is hoping to mortgage for a $400 million spring debt payment.

Christian de Portzamparc: Little known in the U.S. outside architecture devotees, de Portzamparc is notable for the LVMH Tower in New York and the breathtaking concert hall for the Luxembourg Philharmonic. His design for the opera house in Rio de Janeiro will be an instant landmark.

KieranTimberlake: The firm's "Cellophane House" was the hit of MoMA's prefab home show last summer.

Olsen Sundberg Kundig Allen: This Seattle firm boasts a dossier of important public buildings, but what we love most: a skillful hand with -residences framing sub-lime natural vistas.